Seminar - Direct Human Brain Recordings and the Neural Basis of Conceptual Representations
Date: February 11, 2011
Time: 4:00 PM
Location: Matheson Hall, Room: 109
Joshua Jacobs, Ph.D.
School of Biomedical Engineering, Science, and Health Systems
Dr. Jacobs will give an overview of his research examining the neural basis of cognitive processes using direct brain recordings from epilepsy patients. These patients have surgically implanted electrodes that provide detailed data on the neural basis of human cognition. With this technique, he has identified novel patterns of human brain activity that encode abstract conceptual information and were unexpected on the basis of studies in animals. First, Dr. Jacobs will discuss his work on spatial navigation, where he discovered a class of human neurons whose activities encode the concept of whether a navigational route is "clockwise" or "counterclockwise." Then, he will focus on human electrocorticographic (ECoG) recordings, which reveal the combined activity of groups of neurons. Dr. Jacobs will explain how ECoG data reveal the timing and rate of single-neuron spiking. Furthermore, he will describe his new discovery that high-frequency ECoG activity reveals neuronal patterns that distinguish individual cognitive states, including representations of both perceptual and conceptual information. Finally, using a case study in one notable patient, Dr. Jacobs will describe the close relation between high-frequency ECoG activity at a particular recording site and the cognitive state that is elicited when the site is stimulated.
Joshua Jacobs, Ph.D., earned Bachelors and Masters degrees in Computer Science at MIT from 1997 to 2002. His Masters dissertation examined algorithms for dynamically improving software performance. In 2002–2003, Dr. Jacobs worked at Bloomberg L.P. as a senior level software developer. Dr. Jacobs entered graduate school at the University of Pennsylvania in 2004. During graduate school he published in three areas of human neuroscience: scalp electroencephalography (EEG), single-neuron recordings, and electrocorticography (ECoG). He built a scalp EEG recording system that performed real-time data analysis and published two scalp EEG papers, one in collaboration with Dr. Tim Curran from U. Colorado (Jacobs et al., 2006; Hwang et al., 2005). From 2004–2008, Dr. Jacobs collaborated with Dr. Itzhak Fried at UCLA, examining recordings of single-neuron activity from epilepsy patients during spatial navigation. Through this research hr learned methods for recording human neuronal spiking and became familiar with the literature on the electrophysiology of the hippocampus during spatial navigation. This collaboration led to five publications (Jacobs et al., 2007; Ekstrom et al., 2007; Manning et al., 2009; Jacobs, Korolev, et al., 2010; Jacobs, Kahana, et al., 2010). In 2008, Dr. Jacobs began a new line of research studying specific cognitive states with ECoG. Through this work he demonstrated that ECoG data reveal particular neuronal network states (Jacobs & Kahana, 2009) and can identify neural correlates of specific semantic information (for review, see Jacobs & Kahana, 2010). Dr. Jacobs found this approach extremely promising and decided to make it the centerpiece of his future research.
Matheson Hall is located at 32nd and Market Streets.